I HAVE A STARTING ISSUE - ANYONE KNOW WHAT IS WRONG? on 1997 Ford Aspire

SOMETIMES IT WILL START FINE, OTHER TIMES IT WILL TURN OVER BUT NOT START, AND THEN I CAN TURN THE KEY AND THERE IS NOTHING BUT A CLICK. I DO NOT WANT TO REPLACE THE STARTER IF THAT IS NOT WHAT IT IS. ANYONE HAVE ANY IDEAS? THANKS!